Lou Schuler, co-author with Alwyn Cosgrove of The New Rules of Lifting for Abs (Avery, 2010), hasn’t done one in 10 years. “The idea of doing crunches and sit-ups is to make the abdominal muscles bigger,” he says. “But we all have muscles there. My son had a six-pack for most of his childhood, without doing a single sit-up. He was just a skinny, active kid.” It’s not breaking news that diet (ditch the sugar and refined carbs) is more important than exercise if you want a torso that looks like a box of steaks. But most guys probably don’t realise the most effective moves for chiselling the rectus abdominis aren’t crunches or sit-ups — which can do more harm than good (see opposite). The best exercise to target your gut does the exact opposite of a crunch.

According to a study published in the Journal of Orthopaedic & Sports Physical Therapy last year, the Swiss ball rollout, in which you place your fists on a ball and extend your body like a bridge, is much better than the crunch for creating a ripped stomach and building strong lower-back muscles to support your spine.

But the rollout isn’t new; it’s simply a dynamic tweak of the plank, one of the oldest exercises in the book. In a crunch, you bend your spine. In a plank, you brace it. That makes all the difference.

A pair of studies from 2006 and 2008 show moves like the rollout work the upper and lower abs about 25 per cent more efficiently than a crunch or a sit-up.

The basic plank — toes and forearms on the floor, shoulder blades back and down, bum down, body straight — is harder than you might realise. But once you can hold it for 60 to 90 seconds, move on to a more challenging version. The exercises opposite are organised in ascending order of difficulty — do them in front of a mirror to monitor your form, and be sure to break when it goes off.

Before we reveal the rules for summer abs. Here are five reasons to quit sit-ups:

Contrary to popular belief, sit-ups don’t protect your back. Studies show that building static back strength is the key to preventing injury.

Sit-ups and crunches actually compress your spine more than is allowed by typical oh&s standards.

You risk even more damage if you do a sit-up on a swiss ball — hyper-extending your back below its midline is a no-no.

Flexing forward at the waist is also a bad idea. your abs were designed to be a rigid hoop to support your spine.

Sit-ups are a far less effective abs exercise than planks, which work your six-pack and obliques up to 25 per cent more efficiently.

Launch the gallery to read about and view the five rules for summer abs.

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